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(TMS570)
Hello,
In the doc, it is said: « FreeRTOS requires exclusive use of RTI channel 0, SWI instructions, and System Software Interrupt (SSI) 0 ».
I understand for the RTI of course, but what is the purpose of SWI and SSI ?
Greping for SWI I see #pragma SWI_ALIAS( vPortYield, 0 ) so SWI is used for yield.
Greping for SSI I see #define portYIELDWITHINAPI() { portSYSSSIR1REG = portSYSSSIR1SSKEY; asm( " DSB " ); asm( " ISB " ); } and #define portYIELDFROMISR( x ) if( x != pdFALSE ){ portSYSSSIR1REG = portSYSSSIR1SSKEY; ( void ) portSYSSSIR1REG; } so this is also used for yielding. So it looks like an application yield is using SWI and RTOS yield is using SSI.
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